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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

82                                   ALASKAN GLACIER STUDIES
nature and significance can best be stated by showing the condition of the area in the several periods of observation, namely in 1890 and 1891 by Russell, in 1905 and 1906 by the U. S. Geological Survey parties, and in 1909 and 1910 by the National Geographic Society expedition.
Conditions in 1890-1891. In his expedition of 1890 Professor Russell landed on the west side of Yakutat Bay near Galiano Glacier, and he has given us both a description of it and several photographs in 1890 and 1891 from which we can determine its principal characteristics. He states,1 for example, that "a little way back from the shore clumps of alders, interspersed with spruce trees, marked the beginning of the forest which covered the hills toward the west and southwest." Near this rose a densely wooded hill "about 300 feet high, with a curving outline, convex southward," which lay "at the mouth of a steep gorge in the hills," plainly referring to the Galiano valley. Attracted |                 *            by the peculiar appearance of the hill he forced his way "through the dense thickets"
i                              to its iop where he "found a large kettle-shaped depression, the sides of which were solid
'                              walls of ice 50 feet high."   Continuing toward the "steep gorge in the hills" he forced
]                              his "way for nearly a mile through dense thickets" before reaching the "broad open
:                              fields of rock and dirt" which "completely conceal the ice and form a barren, rugged
surface, the picture of desolation."
!                                  This description does not fit any conditions existing in this vicinity in 1905 or later
years, and we might suspect that some other region was referred to were it not for the
:                               fact that Russell's photographs show clearly that the outer Galiano Glacier at that time
was covered with vegetation.   In his photographs the entire visible bulb beyond the
;                               mountains is darkened by vegetation (PI. XXIX).   From these photographs it is
evident that the continuous vegetation extended well within the mountain valley, and
on the inner side became thinner, and was then succeeded by isolated patches, and
;                               finally by the moraine desert.   This vegetation on Galiano Glacier bulb is shown in a
1                               Boundary Survey photograph in 1895, also proving that the vegetation was present four
1                               years before the 1899 earthquakes.   The same photograph shows vegetation out be-
j                               yond the present bulb of Galiano Glacier where now there is only a barren alluvial fan.
Russell's photographs also show an even-surfaced alluvial fan continuous in 1890 and
1891 from the visible margin of the piedmont bulb southward for two miles or more.
Over this fan the waters of Esker Stream and the stream from the western margin
i                               of Galiano Glacier flowed in many distributaries.   The surface of the fan was diversified
•                               only by the stream channels and was so smooth that the streams were evidently shifting
i                               constantly, for no vegetation, not even annual plants, grew over most of the surface.
j                               It was such a perfect alluvial fan that one would never suspect that it was built on glacier
j                               ice.   Two small, low patches of alder and two low, narrow, alder-covered ridges rose
above a portion of the alluvial fan near the sea, proving that these sections rose high enough
to be above the reach of the .shifting streams; but there is no indication as to their nature.
Probably, however, they represent moraine knolls and ridges not yet consumed or buried
by the fan-building streams.   One of Russell's photographs was taken from a gravel knoll
!                               which remained in 1905 and 1909.   It is an overridden gravel remnant, bearing bowlders
j                               and till on its surface, showing that after its formation it was covered by glacier ice.
j                                   Conditions in. 1905.   When we visited this region in 1905 it required only a glance to
i                               see that there had been important changes in the interval of 15 years since Russell's
»EusaeU, I. C., An Expedition to Mount St. Elias, Alaska, Nat. Geog. Mag., "Vol. Ill, 1891, pp. 86-89.